Means of escape:

The means of escape can start at any point inside a building where there may be people.     

The means of escape end when 'ultimate safety' is attained outside the building.   This ultimate safety has to be far enough from the building to ensure that people in the safe area are not exposed to radiated heat, smoke or any other fire threat.

A building can be considered to have safe means of escape if everyone in the building can achieve one of the three aims in the following chart.  People do not have to be able to achieve all of the aims, one will suffice. But if anyone cannot achieve any of the aims then the building is not safe for that person.